Hydrolysis of Fatty Acid Esters by Candida Antarctica Lipase B (Novozym 435) Dissolved in Anhydrous Triethylamine

Abstract

AbstractEnzyme‐catalyzed stereoselective esterification of OH groups in non‐aqueous media has been widely used for kinetic racemate resolution. However, rapid hydrolysis of the ester group was observed as a competing reaction if we attempted to resolve 3‐hydroxy octanoic acid methyl ester with Novozym 435 in a non‐aqueous medium with a catalytic amount of the base triethylamine. This hydrolysis away from the stereogenic carbon atom showed stereoselectivity, thus the preparative value of this reaction was inspected closer and it could be extended to higher homologues. 3‐Hydroxy decanoic acid methyl ester, 3‐hydroxy dodecanoic acid methyl ester and 3‐hydroxy tetradecanoic acid methyl ester were also hydrolyzed by Novozym 435 with enhanced reaction rates and moderate selectivities if dissolved in triethylamine. Ethyl mandelate and ethyl lactate were also converted under these conditions. The same phenomenon could also be observed with a 2 % DABCO solution in hexane, whereas secondary amines, for example piperidine, did not influence the reaction.